The present invention relates to the refrigeration system utilized in a refrigerator and in particular relates to a support tube for supporting a refrigerant suction tube within a refrigerator cabinet.
In the construction of a domestic refrigerator, it is common practice to locate the evaporator coil of the refrigerator system in close proximity to the freezer compartment of the refrigerator. In some instances, the evaporator coil is mounted adjacent the rear wall of the inner liner of the refrigerator cabinet and is covered by a cover plate. Alternatively, the mullion divider between the fresh food compartment and the freezer compartment of the refrigerator is adapted to house the evaporator coil. Circulation of air by a fan located in the evaporator housing forces air over the evaporator coil to cool the fresh food and freezer compartments.
In this type of refrigerant system, a compressor motor is mounted at the bottom at the refrigerator cabinet below the outer shell. The compressor motor receives refrigerant from the evaporator coils through a suction refrigerant tube. The suction refrigerant tube is either mounted on the exterior of the back wall of the outer shell of the cabinet or is positioned within the outer wall of the cabinet, behind the rear wall of the inner liner and within the foam in place insulation. Both of these placements of the suction tube have associated disadvantages. When the suction refrigerant tube passes from the evaporator coil through the rear walls of the inner liner and the outer shell, the suction tube extends down along the outer rear wall of the refrigerator cabinet spaced therefrom. The protrusion of the suction tube is both unpleasantly visible and limits the distance that the refrigerator cabinet can be pushed back towards a kitchen wall. When the refrigerant suction tube passes from the evaporator coil through the inner liner of the refrigerator and down a foam filled cavity located between the inner liner and the rear wall of the outer shell to the compressor motor, the suction tube cannot be readily replaced and is not accessible for field servicing. Further, this arrangement has the disadvantage that the suction tube typically is located spaced from the rear wall of the refrigerator liner and may be shifted closer to the rear wall during the foaming operation resulting in sweating along the rear wall.
Clearly, a refrigerant suction tube having the advantages of serviceability at a later date, non-sweating, and not having any visual appearance or effect over the positioning of the refrigerator cabinet relative to a kitchen wall would be advantageous.
The present invention relates to the use of a support tube mounted within the foam in place insulation located within a refrigerator cabinet. The support tube extends from a refrigerant tube access opening in the rear wall of the inner liner of the refrigerator, within a rear cavity located between the inner liner of the refrigerator cabinet and an exterior or outer shell for the refrigerator cabinet and through an exit opening in a bottom wall of the outer shell adjacent a compressor motor housing. The tube extends into and through this exit opening in the outer shell. The purpose of the tube is to allow a passageway through which a refrigerant tube in the form of suction tube may be slid through and secured in place during the manufacture of the refrigerator.
By having such a support tube with a refrigerant tube being inserted and extending therethrough, serviceability of the refrigerant tube in the field at a later time during the life of the refrigerator is readily available to a service operator. Further, the support tube is positively located within the rear cavity and is not subject to shifting during the foaming operation. Consequently, the refrigerant tube is positively located within the support tube and hence is not subject to shifting during the foaming operation which for most practical purposes eliminates sweating associated with shifting of the refrigerant tube. Also, with the support tube housing the refrigerant tube spaced within the insulation, there is no unsightly protruding suction tube beyond the back wall of the outer shell casing of the refrigerator cabinet.
In order to facilitate the insertion of the refrigerant tube within the support tube, which may either be a plastic or metallic tube, the refrigerant tube access in the rear wall of the liner has an elliptical shape with a vertical diameter that is larger than the horizontal diameter. The support tube will have a corresponding shape. Further, the support tube does not bend at a right angle as it extends from the rear wall of the inner liner and is instead gently curved from the rear wall of the inner liner. This gentle curvature and the elliptical shape allows for the refrigerant tubing to be inserted and slid downwardly along the support tube without the suction tube buckling. It should be understood that the diameter and wall thickness of the refrigerant suction tubing can result in easy bending of this tube. Accordingly, the elliptical shape of the liner access opening and the gentle curvature of the support tube facilitate the insertion of the refrigerant tube through the support tube.
The support tube has a first end that is extends through the bottom wall exit opening of the outer shell of the refrigerator. This first end of the support tube includes a flange like shoulder that locates and seals the support tube relative to the bottom wall of the exit opening.
The refrigerator cabinet may further include a support block of insulation material that is mounted to the rear wall of the inner liner within the rear cavity. The support block has a gently curved passageway that extends from the refrigerant tube access opening of the inner liner to a lower port facing into the rear cavity. The support tube is adapted to pass through this passageway in the insulation block and to be held by the support block adjacent the refrigerator tube access opening in the liner. Further, the support block is held against the inner liner by an oval shaped stick-on adhesive gasket that surrounds the refrigerant tube access opening and is fixed between the support block and the inner liner. The support block may also be held against the outer shell by at least one stick-on gasket.
During the manufacture of the refrigerator cabinet, the support block is mounted to the back wall of the outer shell at a predetermined location by the at least one first stick-on gasket. The support tube is inserted through the bottom wall exit opening in the cabinet outer shell and the support tube is then passed into the lower port of the support block and follows this passageway until the support tube extends substantially through, if not all the way through, the support block passageway. At this time, the shoulder flange of the other first end of the support tube is brought into engagement with the bottom wall and dimples in the outer shell of the cabinet. Next, the inner liner is mounted into the open front of the outer shell such that the refrigerant tube access opening in the rear wall of the inner liner is positioned substantially adjacent to the corresponding opening in the support tube. Also, a single sided, or double sided, sticking oval gasket is mounted to the block surrounding the oval tube such that when the liner is pressed against the block, the oval gasket seals the liner to the block.
In accordance with an aspect of the present invention there is provided a refrigerator cabinet comprising an outer shell having at least a back wall, a bottom wall and a first open front. The cabinet comprises a inner liner having at least opposing side walls, a rear wall and a second open front, the inner liner is positioned within the outer shell and defines a rear cavity between the rear wall of the inner liner and the back wall of the outer shell. A compressor motor housing is located below the bottom wall of the outer shell. The bottom wall of the outer shell has an exit opening between the rear cavity and the compressor motor housing. An evaporator housing is adapted to carry an evaporator coil and is positioned within the second open front of the inner liner adjacent the rear wall. A refrigerant tube access opening is in the rear wall of the inner liner adjacent the location where the evaporator housing meets the rear wall of the liner. A support tube extends from the refrigerant tube access opening in the rear wall of the inner liner within the rear cavity, through the exit opening of the outer shell and into the compressor motor housing. Foamed in place insulation is in the rear cavity and covers the support tube. A refrigerant tube extends from the evaporator housing to the compressor motor housing through the refrigerant tube access opening in the rear wall of the inner liner, through the support tube and through the exit opening in the bottom wall of the outer shell.